Démonstration génétique de l'inversion fonctionnelle du phénotype sexuel femelle sous l'action de la température d'élevage chez l'Amphibien Urodèle : Pleurodeles waltlii Michah

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Thermosensibilité de la différenciation sexuelle chez l'Amphibien Urodèle, Pleurodeles waltlii Michah. Conditions pour obtenir l'inversion du phénotype sexuel de toutes les femelles génétiques sous l'action de la température d'élevage

Contemporary social policy relating to women\u27s employment remains strikingly ambivalent. Those in favor of traditional family structures, a position that is generally associated with conservative political agendas, have often expressed a preference for a family model that emphasizes the woman\u27s role as a homemaker, or to use the more recent term, a caretaker. At the same time, as the 1996 Welfare Reform Act demonstrates, if the choice is between providing financial support that would enable lower-income women to stay in the home and forcing those women into the labor market, the conservative agenda will opt for the latter. More recently, and as an adjunct to the continuing welfare reform, policy makers on the right have advocated policies intended to promote marriage as a means of reducing poverty and providing for a more stable home for children. In some ways, these marriage promotion policies can be seen as a substitute for employment and as a way of striking a balance between the competing goals entangled in the welfare debate. Although these specific marriage proposals are of recent vintage, the objectives on the right, of promoting traditional families while deemphasizing women\u27s role in the labor market, are familiar and long-standing. What has been more surprising is the convergence of policy objectives with the developing interest on the left of support for women\u27s caretaking roles with public subsidies. In the last several years, there has been a veritable explosion of books and articles emphasizing women\u27s role as caretakers and the difficulties women have balancing their roles as mothers and paid wage earners. As a way of ensuring a better balance between what are typically seen as two distinct roles, this literature suggests that it would be a desirable social policy to facilitate women\u27s caretaking, through more extended parental leave, nonmarginalized part-time work, and by placing a greater social value on caretaking. These proposals, however, would likely have a serious negative effect on the quest for greater equality for women, particularly in the workplace, and they are likely to produce a replay of the debate over “difference” feminism from the 1980s by identifying women as caretakers and by appearing to accept gendered differences. Just as is true of the marriage proposals on the right, these policy suggestions might signal a return to the past rather than a move forward for women. The right\u27s marriage proposals and the left\u27s carework proposals nonetheless appear to focus on different aspects of women\u27s roles. As the left recognizes, women can be mothers without being wives and support for caretaking is an unquestionably important social goal, which the left acknowledges through its advocacy of public responsibility for caretaking. The right, on the other hand, is attempting to force mothers to be wives while continuing to devalue the caretaking done by poor women by decreasing public support for caretaking. The proposals do, however, have a similar effect; each set of proposals can be seen as reinforcing, and in some ways reifying, women\u27s role within the home. While we support the goal of providing increased recognition to the value of caretaking, we contend that this revaluation should be achieved without diminishing the role of women in the workplace. First, we challenge the view that marriage provides a cure for welfare dependence. Second, we argue that in addition to stressing the importance of caretaking, the left should focus on other issues that affect women\u27s equality, such as education, the timing and length of the school calendar, and continued workplace discrimination. It is important to recognize that much of the carework literature does, of course, challenge the gendered nature of the workplace and in this essay we are challenging one aspect of the literature, that which focuses on facilitating women\u27s carework. Our goal is to change the gendered female character of carework; although we approach the issue from outside of the home, we also seek to facilitate men\u27s performance of household work and women\u27s performance of market work

Expression d'une protéine liée au sexe, la peptidase-1, chez des Pleurodcles femelles soumises à un vol orbital et recherche d'anomalies génétiques dans leurs descendances

The "Experience Triton" embarked on board of Biosatellite Cosmos 2229 (or Bion 10) pooled several experiments engaged by different teams. Our laboratories have to study in the amphibian urodele Pleurodeles waltl : 1- the expression of a sex-linked enzyme, the peptidase-1, in embarked and synchrone control females. The electrophoretical patterns of the enzyme in ovary, gut and muscles of flight samples were similar to erythrocyte controls but they were slightly different for kidney and heart. 2- the detection of possible genetic abnormalities in the offspring of females submitted to space environment. Embarked females and synchrone females were used as donors of ovaries both to castrated adult females and juveniles males. In may 1994, one recipient female and 6 recipient males are alive in may 1994. Laparotomy of the host animals allowed to oversee the success of the graft for all the surviving animals excepted one male which had received an ovary of an embarked female.Because of the slow development of ovaries in Pleurodeles , the success of this space experiment cannot be ascertain before the reproduction of these animals which will conduct in some monthsL' "Expérience Triton" embarquée à bord du Biosatellite Cosmos 2229 (ou Bion 10) regroupait plusieurs équipes scientifiques russes et françaises. Nos laboratoires avaient à étudier chez FAmphibien Urodèle Pleurodeles waltl : 1-l'expression d'une enzyme liée au sexe, la peptidase-1, chez des femelles spatialisées et chez leurs contrôles synchrones au sol. Les patterns électrophorétiques de l'enzyme obtenus pour l'ovaire, l'intestin et les muscles abdominaux sont semblables au pattern de référence établi à partir des érythrocytes d'animaux témoins. En revanche, le pattern est différent pour le rein et le coeur. Aucune différence majeure n'a été décelée entre les patterns des animaux du vol orbital et ceux de leurs contrôles synchrones. L'activité enzymatique spécifique ne présente pas de différences significatives entre les animaux du vol et ceux du lot synchrone pour l'ovaire, l'intestin, le coeur et les muscles; dans les reins, l'activité parait plus élevée pour les femelles du vol que pour celles du lot synchrone. 2- la recherche d'anomalies génétiques dans la descendance des femelles soumises aux contraintes de l'environnement spatial, et plus particulièrement à la microgravité et au rayonnement cosmique. Selon le protocole retenu pour la mission, toutes les femelles embarquées devaient être sacrifiées après leur retour sur Terre. Aussi leurs ovaires ont été transplantés dans des femelles adultes castrées ou des mâles juvéniles castrés. En mai 1994, une femelle et 6 mâles greffés sont en vie. Chez la femelle et 5 mâles, le succès des greffes a été constaté à partir de laparotomies pratiquées sur les animaux. Le développement des ovaires étant très lent chez le Pleurodèle, l'obtention et l'analyse des descendances des animaux greffés ne peuvent pas être envisagées avant quelques moi